There were two mysterious sudden spikes in carbon 14 in tree rings around a thousand years ago. Now some researchers at Lund University say they’ve matched those to beryllium layers in ice cores from the Arctic and Antarctic. Some wild event made these changes across continents all over the world at the same time, and about the only thing that could have done that was a massive solar storm (or two). There are estimates these extreme storms would have been ten times stronger than the biggest solar storms we have had in the last few decades. The two big bad storms are described as a few times bigger than even the largest solar storm in modern history, which was The Carrington Event in 1859. The radioactive spikes specifically show up in tree rings in 774/775AD and 993/994AD. It’s pretty cool that we can pin those years down so accurately, and as an aside, I imagine it makes a fairly handy calibration point for tree ring researchers now that we know it was global.
Unfortunately, if one of those happened now, it would not be fun. The [...]